BESTFIT Mainspring 210H for Gruen caliber 405, 406, 410, 411, etc - Alloy

BESTFIT Mainspring 210H for Gruen caliber 405, 406, 410, 411, 420, 421, 426 plus perhaps more Gruens and similar ébauche watches, white alloy. See image for precise mainspring specifications. I likely have several of these so the one you get may differ slightly from the images. I specialize in hard to find watch parts so I usually have whatever you might need and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.